Ryan Zinke, the Interior Secretary, has been criticised over a $139,000 bill to the taxpayer for new office doors.

Kellyanne Conway, the president's counselor, is also under pressure after it emerged she flew on some of the costly military flights and private jets that saw Tom Price resign as health secretary last year.

Mr Shulkin, Mr Carson, Mr Zinke, and others in the cabinet have recently been receiving training on ethics rules from senior White House officials after details of their spending emerged.

As White House aides nervously waited to see if Mr Trump would strike Friday, there was room for some gallows humour. One source told CNN: “Everyone loves a season finale.”

Sarah Sanders, Mr Trump's press secretary, said chief of staff John Kelly had spoken with White House staff on Friday morning.

She said Mr Kelly "reassured them there were no immediate personnel changes at this time and that people shouldn't be concerned."

Mrs Sanders said she spoke to the president about General McMaster on Thursday night and he had "no intention of changing" and "looked forward to continuing working with him".

She said the president and General McMaster had been in meetings on Friday, but she did not know if the issue of his position came up.

Mrs Sanders described the national security adviser as a "dedicated public servant who is not focused on the news stories but big issues like North Korea, Russia and Iran".